Sewing-machine.



F. OHATFIELD.

' SEWING MACHINE. APPLIG'ATION FILED MAY 25, 1907.

Patented June 14, 1910.

3 SHEETSSHEET 1, f

I I w [V/f/VfSSES t I F/il/IV 67/ HELD v Z 6M HAS/77 7' P. GHATFIELD.SEWING MACHINE. APPLICATION FILED MAY 25, 1907.

Patented June 14, 1910.

3 SHEETSSHEET 2.

P. UHATFIELD. SEWING MACHINE.

APPLIOATION FILED MAY 25, 1907.

Patented June 14,1910.

3 SHEETSSHEET 3.

UNITED STATES PATENT OFFICE.

FRANKLIN GI-IATFIELD, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR TONORTHWESTERN KNITTING 00., 0F MINNEAPOLIS, MINNESOTA, A CORPORATION.

SEWING-MACHINE.

Specification of Letters Patent.

Patented June 14, 1910.

To all whom it may concern:

Be it known that I, FRANKLIN CHA'rrmLD, of Minneapolis, in the county ofHennepin, State of Minnesota, have invented certain new and usefulImprovements in Sewing- Machines, of which the following is aspecificat-ion.

This invention relates to improvements in single or multiple needlesewing machines, and the objects of the invention are to provide amachine by which a seam may be formed with a single thread or a seriesof threads extending through the material and with additional threadslooped back and forth on both sides of the material through the stitchesformed by the thread or series of threads. The invention consistsgenerally in the constructions and combinations hereinafter describedand particularly pointed out in the claims.

In the accompanying drawings, forming part of this specification; Figure1 is a vertical section of a portion of a sewing-machine embodying myinvention. Fig. 2 is a transverse section on the line 2-2 of Fig. 1looking in the direction of the arrow. Fig. 3 is a detail view of aportion of the machine shown in Fig. 1 with the parts in a differentposition. Fig. 4 is a front view of the parts of the machine shown inFig. 3, said parts being in the same position that they are in Fig. 3.Fig. 5 is a front sectional view of the machine. Fig. 6 is a detail planof the same. Fig. 7 is a top view and Fig. 8 an underside view of theseam formed by the machine. Figs. 9, 10, 11 and 12 are respective detailviews showing the movements of the parts of the machine. Fig. 13 is aview on an enlarged scale of a portion of the seam formed by the machineand illustrating the manner in which the under thread is looped throughthe stitches. Fig. 14 is a detail view of the spreader.

In all of the drawings, 2 represents the frame of the machine, 3 thepresser foot, 4 the feed-plate, 5 the needle-bar and 6, 6, 6 the needleswhich are preferably three in number and arranged as shown in Figs. 2,4, and 5 with the points of the needles at difierent distances from theneedle-bar. This arrangement is usually secured by setting the needlesin the base at different depths, as shown in Fig. 2. I prefer to employone or more thread carriers arranged above the throat-plate andoperating to lay the threads diagonally across the seam so that saidthreads are engaged by the threads forming the stitches. I may use asingle thread carrier in which case but a single thread will be laidacross the seam. As shown in the drawings, provide two thread carriers 7and 8, each of which carries a thread, and these carriers have theirends moved back and forth across the seam, said movement being securedby suitable cams so that the threads 9 and 10 moved by said carriers arelaid diagonally across the seam and engaged by threads forming thestitches, as shown in Fig. 7 of the drawings. I have shown in thedrawings, and prefer to use, a series of needles carrying the threadsforming the stitches, but the invention may be employed with a singleneedle if desired. Each of the needles 6, 6, 6 is provided with athread, in the usual manner, and said needles are simultaneouslyreciprocat-ed, passing through the material and causlng the threadspassing through said material, to form parallel rows of stitches.

For the purpose of passing a thread through the loops of the stitches,as shown particularly in Fig. 13 of the drawings, I provide areciprocating looper 9 that is arranged below the throat-plate andcarries a thread which it passes through the loops of all the stitchesformed by the needles 6, 6, 6. This looper 9 is preferably of curvedform (see Fig. 5) and is offset and stands at a slight angle to avertical plane passing through the three needles (see Fig. 6). The

looper is secured upon a rocker arm 10 which is pivotally supported at11 on the base-plate 12. This rocker arm is preferably of invertedL-shape, and is provided with the sockets 13 in which the looper 9 ismounted. A connecting rod or pitman rod 14 is pivotally connected tothis rocker arm and is adapted to be operated from any suitable drivingpart of the machine. The means for operating the pitman are not shown.This rocker armis also provided with the lugs l5'15 in which are mounteda shaft 16, the axis of this shaft standing at right angles with theaxis of the pivot of the rocker arm. The looper 9 is provided with aneye 9 near its point and with a second eye 9 in its shank just below itsforwardly extending curved part (see Fig.

9). The thread 10 passes through both of these eyes in the looper andextends from the eye 9' to the eye 9 under the curved portion of thelooper.

A spreader 17 is mounted on the shaft 16. This spreader preferablyconsists of a curved arm having a hook 18 at its free end. The end ofthe hook is preferably beveled off at one side, as shown in the detaileddrawing, Fig. 14. A rocking standard 19 is pivotally mounted in asupport on the base-plate. This standard is located at one side and infront of the rocker arm 10.

A curved arm 20 is secured to one end of the short shaft 16, with itsopposite end pivotally connected to the upper part of the standard 19. Iprefer to provide each end of the standard 19 with a ball-joint,consisting of the two members 21 and 23. The member 21 is provided witha take-up screw 22 by means of which wear between the two members of theball-joint may be taken up. At its lower end, the standard is supportedby a bolt 24 passing through the member 23 of the ball-joint and into aslot 25 in a block 26 on the base-plate. This slotted connection permitsthe lower end of the standard to be adjusted toward or from the pivot ofthe rocker arm 10. The end of the curved arm 20 is preferably connectedto the balljoint member 23 in the upper end of the standard 19 by ascrew 27. The opposite end of the shaft 16 is provided with a crank arm28 having an eye 29 for the passage of a thread. This arm forms apull-off for the under thread.

I have not considered it necessary to show the means for operating theneedle-bar, or for operating the thread carriers above the throat-plate,as such means are well understood in the art and form no part of myinvention, nor have I considered it necessary to show the means forreciprocating the pit man or connecting rod 14.

Operation: The multiple needle-bar is vertically reciprocated by anysuitable means, and the thread carriers above the throatplate are swungacross the seam so as to cause the threads carried by them to be laidback and forth across the seam and to be engaged by the loops of thestitches, as shown in Fig. 7 of the drawings. A reciprocating motion isgiven to the pitman 14, which causes the rocker-arm 10 to be rockedforward and back, and this imparts a forward and back movement to thelooper 9. At the same time the spreader 17 is moved forward and back inunison with the looper, and as the rocking of the standard 19 throughthe arm 20 also imparts a rocking motion to the shaft 16, the spreader17 is caused to move toward and from the looper 9. Four positions of theneedles, the looper and the spreader, are shown in Figs. 9, 10, 11 and12 of the drawings.

I will describe the operation of the mechanism beginning with the partsin the position shown in Fig. 9 of the drawings in which the needles areshown in their lowermost position with the looper and spreader retractedand the threads in the position which they assume when the needles andlooper are thus situated. It will be seen that the thread carried by thelooper passes through the pull-off 28, and as the looper advances andthe needles rise, the looper passes between the needles and the threadscarried by them. The intermediate position of the parts is shown in theFig. 10 of the drawings. The looper passes on until it reaches theposition shown in Fig. 11, at which time the needles are at or near theupper end of their movement while the spreader has rocked forward untilthe hook on .the end thereof has passed over the thread on the top ofthe looper, as shown in Fig. 11. The pull-off has also rocked forwardwith the spreader into the position shown in Fig. 11. As the looperbegins to move backward, the spreader rocks away from it and as the hookon the spreader passes over the top of the looper, it engages the threadon the top of the looper and forms a loop by drawing the thread awayfrom the looper. The slack for this loop is provided by the rocking ofthe pull-off with the spreader. WVhile this loop is being formed, thelooper is continuously moving backward and the spreader is both movingbackward simultaneously with the looper and is rocking away from thelooper. During this movement of the looper and spreader, the needles aredescending to form the next series of stitches and when the parts are inthe position shown in Fig. 12 of the drawing, the needle having itspoint lowermost, passes into the loop thus formed between the looper andthe spreader. The thread forming this loop comes in cont-act with theside of the needle and the loop slips oil from the inclined hook on theend of the spreader. The movement of the looper and spreader continuesand the parts then assume the position shown in Fig. 9 of the drawings.This operation is continued and each time the needles descend, thelooper passes between them and the threads that they carry so that thestitches are locked by the loops passing through them on the under sideof the material, as shown in Fig. 13 of the drawing.

I do not limit myself to the details of construction as the same may bevaried in many particulars without departing from my invention.

I claim as my invention:

1. The combination, in a machine of the class described, with a seriesof needles arranged to reciprocate in a common vertical plane, of alooper, means for reciprocating said looper in a plane substantiallyparallel to the plane of said needles, a spreader moving with saidlooper, and means for moving said spreader toward the looper as thelooper reaches the limit of its forward movement, substantially asdescribed and for the purpose set forth.

2. The combination, in a machine of the class described, with athroat-plate, a series of needles arranged in a common vertical planeand means for reciprocating said needles, of a looper arranged belowsaid throatplate, means for reciprocating said looper in a planesubstantially parallel to the plane of said needles, a spreader movingwith said looper, and means for moving said spreader toward the looperas the looper reaches the limit of its forward movement, substantiallyas described and for the purpose set forth.

3. The combination, in a machine of the class described, with a seriesof needles arranged to reciprocate in a common vertical plane, of alooper, means for reciprocating said looper in a plane substantiallyparallel to the plane of said needles, a spreader moving with saidlooper, means for moving said spreader toward the looper as the looperreaches the limit of its forward movement, and a pull-01f, and means formoving said pull-ofi' with said spreader, substantially as described andfor the purpose set forth.

1. In a machine of the class described, the

combination with a suitable throat-plate, a series of needles and meansfor vertically reciprocating the same, of a reciprocating looperarranged beneath said throat-plate and provided with means forreciprocating it in a plane substantially parallel to the plane of saidneedles, a spreader moving with said looper, means for moving saidspreader toward or from said looper and a pull-01f and means for movingsaid pull-ofi" with said spreader, substantially as described. 5. Thecombination, in a machine of the class described, with the series ofneedles, of the looper 9 arranged at a slight angle to a vertical planepassing through said needles, a rocker arm 10 upon which said looper issecured, means for operating said rocker arm, a shaft 16 mounted inbearings upon said rocker arm with its axis at right angles to the axisof the pivot of the rocker-arm, a Spreader 17 mounted on the shaft 16,and means for rocking said shaft 16, in unison with the movement of thesaid rocker arm, for the purpose set forth.

In witness whereof, I have hereunto set my hand.

FRANKLIN CHATFIELD.

